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Njengamanje, azikho izindinganiso eziningi zokuxhumana, ngakolunye uhlangothi, zinelukuluku futhi ziyathakazelisa, ngakolunye uhlangothi, incazelo yazo ayithathi amakhasi angama-500 ngefomethi ye-PDF. Isignali eyodwa enjalo okulula ukuyinquma isignali ye-VHF Omni-directional Radio Beacon (VOR) esetshenziswa ekuzulazuleni emoyeni.
I-VOR Beacon (c) wikimedia.org
Okokuqala, umbuzo wabafundi: ungayenza kanjani isignali ukuze isiqondiso sinqunywe kusetshenziswa i-omnidirectional eyamukela i-antenna? Impendulo ingaphansi kokusika.
Ulwazi General
Uhlelo (VOR) ibilokhu isetshenziselwa ukuzulazula emoyeni kusukela ngeminyaka yama-50s wekhulunyaka elidlule, futhi iqukethe amabhakhoni omsakazo webanga elifushane (100-200 km), esebenza kububanzi befrikhwensi ye-VHF engu-108-117 MHz. Manje, ngesikhathi se-gigahertz, igama elithi imvamisa ephezulu kakhulu maqondana namafrikhwensi anjalo lizwakala lihlekisa futhi likhuluma ngokwalo. ubudala leli zinga, kodwa ngendlela, ama-beacons asasebenza , esebenza ebangeni lamagagasi amaphakathi 400-900 kHz.
Ukubeka i-antenna endizeni kuyaphazamisa ngokwesakhiwo, ngakho-ke inkinga ivele yokuthi ungafaka kanjani ikhodi ulwazi olumayelana nendlela eya kubhakhoni kusiginali ngokwayo. Isimiso sokusebenza "eminweni" singachazwa kanje. Ake sicabange ukuthi sinesibani esivamile esithumela isibani esincane sokukhanya okuluhlaza, isibani saso sizungeza isikhathi esingu-1 ngomzuzu. Ngokusobala, kanye ngomzuzu sizobona ukukhanya kokukhanya, kodwa ukukhanya okukodwa okunjalo akunalo ulwazi oluningi. Ake sengeze owesibili ebhakeni okungaqondile isibani esibomvu esikhanya ngesikhathi lapho umsebe we-lighthouse "udlula" ohlangothini olusenyakatho. Ngoba isikhathi sokukhanya kanye nezixhumanisi zebhakoni ziyaziwa; ngokubala ukubambezeleka phakathi kokukhanya okubomvu nokuluhlaza, ungathola i-azimuth enyakatho. Kulula. Kusele ukwenza into efanayo, kodwa kusetshenziswa umsakazo. Lokhu kwaxazululwa ngokushintsha izigaba. Izimpawu ezimbili zisetshenziselwa ukudlulisa: isigaba sokuqala sihlala njalo (inkomba), isigaba sesibili (okuguquguqukayo) sishintsha ngendlela eyinkimbinkimbi kuye ngokuthi isiqondiso semisebe - i-engeli ngayinye inokushintsha kwesigaba sayo. Ngakho-ke, umamukeli ngamunye uzothola isignali ngokushintsha kwesigaba "sakhe", ngokulingana ne-azimuth kuya kubhakoni. Ubuchwepheshe "be-spatial modulation" benziwa kusetshenziswa i-antenna ekhethekile (Alford Loop, bona i-KDPV) kanye nokushintshashintsha okukhethekile, okukhohlisayo. Okuyikho ngempela isihloko salesi sihloko.
Ake sicabange ukuthi sinebhakhoni evamile yefa, esebenza kusukela ngeminyaka yawo-50s, futhi idlulisela amasiginali ngokuguquguquka okuvamile kwe-AM ngekhodi ye-Morse. Mhlawumbe, ngesinye isikhathi, itilosi empeleni lalilalela lezi zimpawu kuma-headphone futhi limaka izikhombisi-ndlela ngerula nekhampasi ebalazweni. Sifuna ukwengeza imisebenzi emisha kusiginali, kodwa ngendlela yokuthi “singaphuli” ukuhambisana nezindala. Isihloko sijwayelekile, akukho okusha... Senziwe ngendlela elandelayo - ithoni ye-low-frequency engu-30 Hz yengezwe kusignali ye-AM, yenza umsebenzi wesiginali yesigaba sokubhekisela, kanye nengxenye ye-high-frequency, efakwe ikhodi ngokuphindaphindiwe ukuguqulwa kwemvamisa engu-9.96 KHz, kudlulisa isignali yesigaba esiguquguqukayo. Ngokukhetha amasignali amabili nokuqhathanisa izigaba, sithola i-angle oyifunayo kusuka ku-0 kuya ku-360 degrees, okuyi-azimuth oyifunayo. Ngesikhathi esifanayo, konke lokhu ngeke kuphazamise ukulalela i-beacon "ngendlela evamile" futhi kuhlala kuhambisana nabamukeli be-AM abadala.
Masisuke kuthiyori siye kuzijwayeza. Ake sethule isamukeli se-SDR, sikhethe ukushintshashintsha kwe-AM kanye nomkhawulokudonsa ongu-12 KHz. I-VOR beacon frequency ingatholakala kalula ku-inthanethi. Ku-spectrum, isignali ibonakala kanje:
Kulokhu, isignali ye-beacon idluliselwa ngemvamisa ye-113.950 MHz. Phakathi nendawo ungabona ulayini wokuguquguquka kwe-amplitude obonakala kalula kanye namasiginali wekhodi ye-Morse (.- - ... okusho ukuthi i-AMS, i-Amsterdam, i-Schiphol Airport). Ebangeni elingu-9.6 KHz ukusuka kusithwali, iziqongo ezimbili ziyabonakala, zidlulisa isignali yesibili.
Masirekhode isiginali ku-WAV (hhayi i-MP3 - ukucindezela okulahlekile "kuzobulala" sonke isakhiwo sesiginali) futhi siyivule kumsakazo we-GNU.
Ukuqopha
Isinyathelo 1. Masivule ifayela elinesiginali erekhodiwe futhi sisebenzise isihlungi sephasi eliphansi kulo ukuze sithole isiginali yokuqala yesithenjwa. Igrafu ye-GNU Radio iboniswa emfanekisweni.
Umphumela: isignali yefrikhwensi ephansi ku-30 Hz.
Isinyathelo 2: nquma isignali yesigaba esiguquguqukayo. Njengoba kushiwo ngenhla, itholakala ku-9.96 KHz, sidinga ukuyihambisa kufrikhwensi enguziro bese siyiphakela kusibonisi se-FM.
Igrafu yerediyo ye-GNU:
Yilokho kuphela, inkinga ixazululiwe. Sibona amasiginali amabili, umehluko wesigaba okhombisa i-engeli ukusuka kumamukeli ukuya kubhakoni ye-VOR:
Isiginali inomsindo impela, futhi ukuhlunga okwengeziwe kungase kudingeke ukuze ekugcineni ubale umehluko wesigaba, kodwa ngithemba ukuthi isimiso sicacile. Kulabo asebekhohliwe ukuthi umehluko wesigaba unqunywa kanjani, isithombe esivela :
Ngenhlanhla, awudingi ukwenza konke lokhu ngesandla: kukhona kakade ku-Python, ikhipha amasiginali we-VOR kusuka kumafayela we-WAV. Eqinisweni, ukufunda kwakhe kwangikhuthaza ukuba ngifunde lesi sihloko.
Labo abanentshisekelo bangasebenzisa uhlelo kukhonsoli futhi bathole i-engeli eqediwe ngamadigri ukusuka efayeleni eselirekhodiwe:
Abalandeli bezindiza bangakwazi nokwenza esabo isamukeli esiphathekayo besebenzisa i-RTL-SDR kanye ne-Raspberry Pi. Ngendlela, endizeni "yangempela" le nkomba ibukeka kanjena:
Isithombe ©
isiphetho
Izimpawu ezinjalo "kusukela ekhulwini elidlule" ziyathakazelisa nakanjani ukuhlaziya. Okokuqala, zilula impela, i-DRM yesimanje noma, ikakhulukazi, i-GSM, akusakwazeki ukunquma “eminwe yakho”. Bavulekele ukwamukelwa futhi abanabo okhiye noma i-cryptography. Okwesibili, mhlawumbe esikhathini esizayo zizoba umlando futhi zithathelwe indawo yi-satellite navigation kanye nezinhlelo zesimanje zedijithali. Okwesithathu, ukufunda izindinganiso ezinjalo kukuvumela ukuthi ufunde imininingwane ethokozisayo yezobuchwepheshe neyomlando yokuthi izinkinga zaxazululwa kanjani kusetshenziswa ezinye izifunda nesisekelo sezinto zekhulu leminyaka elidlule. Ngakho-ke abanikazi abamukelayo bangalulekwa ukuthi bathole amasiginali anjalo ngenkathi besasebenza.
Njengenjwayelo, ukuhlola okujabulisayo wonke umuntu.
Source: www.habr.com